solution;
[tex]Projectile maximum height=\frac{vo/timessinthetha^{2}}{2g}\\
Range =\frac{(vo)^2\times(2\times\theta )}{g}\\
given,\\
range=8.5\times maximum hight\\
(vo)^2sin(2\times\theta )=\frac{8.5\times(vo\times sin\theta )^2}{g}\\
sin(2\times\theta )=\frac{8.5\times(sin \theta )^2}{2}\\
2\times sun(\theta )\times cos(\theta )=4.25\times(sin \theta )^2\\[/tex][tex]using,
{sin(2\times\theta )=2\times sin(\theta)\cos\theta}\\
2\timescos(theta)=4.25\times sin(theta)\\
tan \theta =\frac{2}{4.25}\\
tan \theta =0.47\\
tan\theta=25.2[/tex]